An aromatic sensory compound, which may be an odorant, aroma, fragrance or flavor, is a chemical compound that has a distinct smell or odor that may be sensed by the olfactory nervous system. A chemical compound has a smell or odor when two conditions are met: the compound needs to be volatile, so it can be transported to the olfactory system in the upper part of the nose, and it needs to be in a sufficiently high concentration to be able to interact with one or more of the olfactory receptors. Insect repellents are also aromatic compounds since insects such as mosquitoes intensely dislike the smell of chemical repellents such as DEET. In fact, a type of olfactory receptor neuron in special antennal sensilla of mosquitoes has been identified and is activated by them.
Fragrance oil(s), also known as aroma oils, aromatic oils, and flavor oils, are blended synthetic aroma compounds or natural essential oils that are diluted with a carrier such as propylene glycol, vegetable oil, or mineral oil. Aromatic oils are used in perfumery, cosmetics, flavoring of food, and in aromatherapy. To some people, synthetic fragrance oils are less desirable than plant-derived essential oils as components of perfume. An essential oil is a concentrated, hydrophobic liquid containing volatile aroma compound from plants. Essential oils are also known as volatile, ethereal oils or aetherolea, or simply as the “oil of” the plant from which they were extracted, such as oil of clove. An oil is “essential” in the sense that it carries a distinctive scent, or essence of the plant. Essential oils as a group do not need to have any specific chemical properties in common, beyond conveying characteristic fragrances.
Essential oils are generally extracted by distillation. Other processes include expression or solvent extraction. They are used in perfumes, cosmetics, soap and other products, for flavoring food and drink, and for scenting incense and household cleaning products. Fragrances useful in the practice of the practice of the present invention have been generally classified as Floral, Soft Floral, Floral Oriental, Oriental, Soft Oriental, Woody Oriental, Mossy Woods, Dry Woods, Citrus, Green and Water.
Various essential oils have been used medicinally at different periods in history. Medical application proposed by those who sell medicinal oils range from skin treatments to remedies for cancer, and are often based on historical use of these oils for these purposes. Such claims of use are now subject to regulation in most countries and as a result have grown more vague in order to stay within these regulations.
Interest in essential oils has revived in recent decades with the popularity of aromatherapy, a branch of alternative medicine which claims that the specific aromas carried by essential oils have curative effects. Oils are volatilized or diluted in a carrier oil and used for example, in massage, diffused in the air by a nebulizer, heated over a candle flame, or burned as incense.
U.S. Pat. No. 6,960,625 to Christensen et. al. discloses and claims a transparent polyurethane-hydrogel composition formulated as an air-freshener application that comprises the reaction product of a pre-polymer and a water-soluble crosslinker in an aqueous solvent with little to no organic solvent. The pre-polymer is present in an amount of no greater than about 5.0 wt. % based on the total weight of all the hydrogel components. The pre-polymer is generally prepared from at least one water-soluble polyol and an isocyanate. The transparent polyurethane-hydrogel composition allegedly has desirable gel physical properties and is useful for an air-freshener application.
U.S. Pat. No. 6,294,162 to Semoff et al. teaches a transparent gel air freshener and method for its' preparation. The gel composition comprises an aqueous gel, a fragrance, a surfactant and a co-solvent. The gel is transparent and free from visible particles and is homogeneous throughout. It has a uniform texture, a continuous structure, and includes volatile scented components. The gel is also capable of suspending solids such as botanicals therein for a decorative effect. The method provides for preparation of a gel air freshener, including the suspension of botanicals therein, while maintaining the clarity, texture, and structure of the gel. The method includes the steps of preparing a gel composition and cooling the gel composition. Botanicals may be added to the gel composition when it has gelled enough to support the botanical on the gel surface.
U.S. Pat. Nos. 7,166,259 to Beam et. al. and 5,695,692 to Kennedy are examples of commercially available plug-in or otherwise electric devices that automatically discharge a fragrance spray into a room for a given period of time.